Predicting Word-Recognition Performance in Noise by Young Listeners with Normal Hearing Using Acoustic, Phonetic, and Lexical Variables

2008 ◽  
Vol 19 (06) ◽  
pp. 507-518 ◽  
Author(s):  
Rachel McArdle ◽  
Richard H. Wilson
Keyword(s):  
Word Recognition ◽  
Recognition Performance ◽  
Normal Hearing ◽  
Neighborhood Density ◽  
Monosyllabic Word ◽  
Speech In Noise ◽  
Monosyllabic Words ◽  
Neighborhood Frequency ◽  
Word Familiarity ◽  
Speech Recognition In Noise

Purpose: To analyze the 50% correct recognition data that were from the Wilson et al (this issue) study and that were obtained from 24 listeners with normal hearing; also to examine whether acoustic, phonetic, or lexical variables can predict recognition performance for monosyllabic words presented in speech-spectrum noise. Research Design: The specific variables are as follows: (a) acoustic variables (i.e., effective root-mean-square sound pressure level, duration), (b) phonetic variables (i.e., consonant features such as manner, place, and voicing for initial and final phonemes; vowel phonemes), and (c) lexical variables (i.e., word frequency, word familiarity, neighborhood density, neighborhood frequency). Data Collection and Analysis: The descriptive, correlational study will examine the influence of acoustic, phonetic, and lexical variables on speech recognition in noise performance. Results: Regression analysis demonstrated that 45% of the variance in the 50% point was accounted for by acoustic and phonetic variables whereas only 3% of the variance was accounted for by lexical variables. These findings suggest that monosyllabic word-recognition-in-noise is more dependent on bottom-up processing than on top-down processing. Conclusions: The results suggest that when speech-in-noise testing is used in a pre- and post-hearing-aid-fitting format, the use of monosyllabic words may be sensitive to changes in audibility resulting from amplification.

A Comparison of Recognition Performances in Speech-Spectrum Noise by Listeners with Normal Hearing on PB-50, CID W-22, NU–6, W-1 Spondaic Words, and Monosyllabic Digits Spoken by the Same Speaker

2008 ◽  
Vol 19 (06) ◽  
pp. 496-506 ◽  
Author(s):  
Richard H. Wilson ◽  
Rachel McArdle ◽  
Heidi Roberts
Keyword(s):  
Word Recognition ◽  
Repeated Measures ◽  
Recognition Performance ◽  
Normal Hearing ◽  
Psychometric Characteristics ◽  
Monosyllabic Word ◽  
Repeated Measures Design ◽  
Word Lists ◽  
Monosyllabic Words ◽  
Speech Spectrum

Background: So that portions of the classic Miller, Heise, and Lichten (1951) study could be replicated, new recorded versions of the words and digits were made because none of the three common monosyllabic word lists (PAL PB-50, CID W-22, and NU–6) contained the 9 monosyllabic digits (1–10, excluding 7) that were used by Miller et al. It is well established that different psychometric characteristics have been observed for different lists and even for the same materials spoken by different speakers. The decision was made to record four lists of each of the three monosyllabic word sets, the monosyllabic digits not included in the three sets of word lists, and the CID W-1 spondaic words. A professional female speaker with a General American dialect recorded the materials during four recording sessions within a 2-week interval. The recording order of the 582 words was random. Purpose: To determine—on listeners with normal hearing—the psychometric properties of the five speech materials presented in speech-spectrum noise. Research Design: A quasi-experimental, repeated-measures design was used. Study Sample: Twenty-four young adult listeners (M = 23 years) with normal pure-tone thresholds (≤20-dB HL at 250 to 8000 Hz) participated. The participants were university students who were unfamiliar with the test materials. Data Collection and Analysis: The 582 words were presented at four signal-to-noise ratios (SNRs; −7-, −2-, 3-, and 8-dB) in speech-spectrum noise fixed at 72-dB SPL. Although the main metric of interest was the 50% point on the function for each word established with the Spearman-Kärber equation (Finney, 1952), the percentage correct on each word at each SNR was evaluated. The psychometric characteristics of the PB-50, CID W-22, and NU–6 monosyllabic word lists were compared with one another, with the CID W-1 spondaic words, and with the 9 monosyllabic digits. Results: Recognition performance on the four lists within each of the three monosyllabic word materials were equivalent, ±0.4 dB. Likewise, word-recognition performance on the PB-50, W-22, and NU–6 word lists were equivalent, ±0.2 dB. The mean recognition performance at the 50% point with the 36 W-1 spondaic words was ˜6.2 dB lower than the 50% point with the monosyllabic words. Recognition performance on the monosyllabic digits was 1–2 dB better than mean performance on the monosyllabic words. Conclusions: Word-recognition performances on the three sets of materials (PB-50, CID W-22, and NU–6) were equivalent, as were the performances on the four lists that make up each of the three materials. Phonetic/phonemic balance does not appear to be an important consideration in the compilation of word-recognition lists used to evaluate the ability of listeners to understand speech.A companion paper examines the acoustic, phonetic/phonological, and lexical variables that may predict the relative ease or difficulty for which these monosyllable words were recognized in noise (McArdle and Wilson, this issue).

Word Recognition with Segmented-Alternated CVC Words

1984 ◽  
Vol 27 (3) ◽  
pp. 378-386 ◽  
Author(s):  
Richard H. Wilson ◽  
John T. Arcos ◽  
Howard C. Jones
Keyword(s):  
Word Recognition ◽  
Recognition Performance ◽  
Normal Hearing ◽  
The Other ◽  
Correct Word ◽  
Computer Technique ◽  
Temporal Characteristics ◽  
Monosyllabic Words ◽  
Test Materials

Consonant-vowel-consonant (CVC) monosyllabic words were segmented at the approximate phoneme boundaries and were presented to subjects with normal hearing in the following sequence: (a) the carrier phrase to both ears, (b) the initial consonant segment to one ear, (c) the vowel segment to the other ear, and (d) the final consonant segment to the ear that received the initial consonant. A computer technique, which is described in detail, was used to develop the test materials. The digital editing did not alter appreciably the spectral or temporal characteristics of the words. A series of four experiments produced a list of 50 words on which 10% correct word recognition was achieved by listeners with normal hearing when the vowel segment or the consonant segments of the words were presented monaurally in isolation. When the speech materials were presented binaurally—that is, the vowel segment in one ear and consonant segments in the other ear—word-recognition performance improved to 90% correct.

scholarly journals Psychometric Characteristics of Spanish Monosyllabic, Bisyllabic, and Trisyllabic Words for Use in Word-Recognition Protocols

2020 ◽  
Vol 31 (07) ◽  
pp. 531-546
Author(s):  
Mitzarie A. Carlo ◽  
Richard H. Wilson ◽  
Albert Villanueva-Reyes
Keyword(s):  
Word Recognition ◽  
Recognition Performance ◽  
Normal Hearing ◽  
Current Data ◽  
Hearing Level ◽  
Psychometric Characteristics ◽  
Plural Form ◽  
Individual Word ◽  
The Mean ◽  
The Individual

Abstract Background English materials for speech audiometry are well established. In Spanish, speech-recognition materials are not standardized with monosyllables, bisyllables, and trisyllables used in word-recognition protocols. Purpose This study aimed to establish the psychometric characteristics of common Spanish monosyllabic, bisyllabic, and trisyllabic words for potential use in word-recognition procedures. Research Design Prospective descriptive study. Study Sample Eighteen adult Puerto Ricans (M = 25.6 years) with normal hearing [M = 7.8-dB hearing level (HL) pure-tone average] were recruited for two experiments. Data Collection and Analyses A digital recording of 575 Spanish words was created (139 monosyllables, 359 bisyllables, and 77 trisyllables), incorporating materials from a variety of Spanish word-recognition lists. Experiment 1 (n = 6) used 25 randomly selected words from each of the three syllabic categories to estimate the presentation level ranges needed to obtain recognition performances over the 10 to 90% range. In Experiment 2 (n = 12) the 575 words were presented over five 1-hour sessions using presentation levels from 0- to 30-dB HL in 5-dB steps (monosyllables), 0- to 25-dB HL in 5-dB steps (bisyllables), and −3- to 17-dB HL in 4-dB steps (trisyllables). The presentation order of both the words and the presentation levels were randomized for each listener. The functions for each listener and each word were fit with polynomial equations from which the 50% points and slopes at the 50% point were calculated. Results The mean 50% points and slopes at 50% were 8.9-dB HL, 4.0%/dB (monosyllables), 6.9-dB HL, 5.1%/dB (bisyllables), and 1.4-dB HL, 6.3%/dB (trisyllables). The Kruskal–Wallis test with Mann–Whitney U post-hoc analysis indicated that the mean 50% points and slopes at the 50% points of the individual word functions were significantly different among the syllabic categories. Although significant differences were observed among the syllabic categories, substantial overlap was noted in the individual word functions, indicating that the psychometric characteristics of the words were not dictated exclusively by the syllabic number. Influences associated with word difficulty, word familiarity, singular and plural form words, phonetic stress patterns, and gender word patterns also were evaluated. Conclusion The main finding was the direct relation between the number of syllables in a word and word-recognition performance. In general, words with more syllables were more easily recognized; there were, however, exceptions. The current data from young adults with normal hearing established the psychometric characteristics of the 575 Spanish words on which the formulation of word lists for both threshold and suprathreshold measures of word-recognition abilities in quiet and in noise and other word-recognition protocols can be based.

Lexical neighborhoods and phonological confusability in cross-dialect word recognition in noise

2010 ◽  
Vol 1 (1) ◽  
Author(s):  
Cynthia G. Clopper ◽  
Janet B. Pierrehumbert ◽  
Terrin N. Tamati
Keyword(s):  
Word Recognition ◽  
Target Word ◽  
Recognition Performance ◽  
Spoken Word Recognition ◽  
Spoken Word ◽  
Neighborhood Density ◽  
Minimal Pair ◽  
Dialect Variation ◽  
Vowel Recognition ◽  
Stimulus Materials

AbstractLexical neighborhood density is a well-known factor affecting phonological categorization in spoken word recognition. The current study examined the interaction between lexical neighborhood density and dialect variation in spoken word recognition in noise. The stimulus materials were real English words produced in two regional American English dialects. To manipulate lexical neighborhood density, target words were selected so that predicted phonological confusions across dialects resulted in real English words in the word-competitor condition and did not result in real English words in the nonword-competitor condition. Word and vowel recognition performance were more accurate in the nonword-competitor condition than the word-competitor condition for both talker dialects. An examination of the responses to specific vowels revealed the role of dialect variation in eliciting this effect. When the predicted phonological confusions were real lexical neighbors, listeners could respond with either the target word or the confusable minimal pair, and were more likely than expected to produce a minimal pair differing from the target by one vowel. When the predicted phonological confusions were not real words, however, the listeners exhibited less lexical competition and responded with the target word or a minimal pair differing by one consonant.

A Picture Identification Task as an Estimate of the Word-Recognition Performance of Nonverbal Adults

1980 ◽  
Vol 45 (2) ◽  
pp. 223-238 ◽  
Author(s):  
Richard H. Wilson ◽  
June K. Antablin
Keyword(s):  
Word Recognition ◽  
Recognition Performance ◽  
Test Word ◽  
Stimulus Presentation ◽  
Identification Task ◽  
Closed Set ◽  
Open Set ◽  
Northwestern University ◽  
Monosyllabic Words ◽  
Picture Identification

The Picture Identification Task was developed to estimate the word-recognition performance of nonverbal adults. Four lists of 50 monosyllabic words each were assembled and recorded. Each test word and three rhyming alternatives were illustrated and photographed in a quadrant arrangement. The task of the patient was to point to the picture representing the recorded word that was presented through the earphone. In the first experiment with young adults, no significant differences were found between the Picture Identification Task and the Northwestern University Auditory Test No. 6 materials in an open-set response paradigm. In the second experiment, the Picture Identification Task with the picture-pointing response was compared with the Northwestern University Auditory Test No. 6 in both an open-set and a closed-set response paradigm. The results from this experiment demonstrated significant differences among the three response tasks. The easiest task was a closed-set response to words, the next was a closed-set response to pictures, and the most difficult task was an open-set response. At high stimulus-presentation levels, however, the three tasks produced similar results. Finally, the clinical use of the Picture Identification Task is described along with preliminary results obtained from 30 patients with various communicative impairments.

Fitting and Verification of Frequency Modulation Systems on Children with Normal Hearing

2014 ◽  
Vol 25 (06) ◽  
pp. 529-540 ◽  
Author(s):  
Erin C. Schafer ◽  
Danielle Bryant ◽  
Katie Sanders ◽  
Nicole Baldus ◽  
Katherine Algier ◽  
...  
Keyword(s):  
Speech Recognition ◽  
Frequency Modulation ◽  
Auditory Processing ◽  
Signal To Noise Ratio ◽  
Recognition Performance ◽  
Normal Hearing ◽  
Signal To Noise ◽  
The Real ◽  
Hearing Sensitivity ◽  
Speech Recognition In Noise

Background: Several recent investigations support the use of frequency modulation (FM) systems in children with normal hearing and auditory processing or listening disorders such as those diagnosed with auditory processing disorders, autism spectrum disorders, attention-deficit hyperactivity disorder, Friedreich ataxia, and dyslexia. The American Academy of Audiology (AAA) published suggested procedures, but these guidelines do not cite research evidence to support the validity of the recommended procedures for fitting and verifying nonoccluding open-ear FM systems on children with normal hearing. Documenting the validity of these fitting procedures is critical to maximize the potential FM-system benefit in the abovementioned populations of children with normal hearing and those with auditory-listening problems. Purpose: The primary goal of this investigation was to determine the validity of the AAA real-ear approach to fitting FM systems on children with normal hearing. The secondary goal of this study was to examine speech-recognition performance in noise and loudness ratings without and with FM systems in children with normal hearing sensitivity. Research Design: A two-group, cross-sectional design was used in the present study. Study Sample: Twenty-six typically functioning children, ages 5–12 yr, with normal hearing sensitivity participated in the study. Intervention: Participants used a nonoccluding open-ear FM receiver during laboratory-based testing. Data Collection and Analysis: Participants completed three laboratory tests: (1) real-ear measures, (2) speech recognition performance in noise, and (3) loudness ratings. Four real-ear measures were conducted to (1) verify that measured output met prescribed-gain targets across the 1000–4000 Hz frequency range for speech stimuli, (2) confirm that the FM-receiver volume did not exceed predicted uncomfortable loudness levels, and (3 and 4) measure changes to the real-ear unaided response when placing the FM receiver in the child’s ear. After completion of the fitting, speech recognition in noise at a –5 signal-to-noise ratio and loudness ratings at a +5 signal-to-noise ratio were measured in four conditions: (1) no FM system, (2) FM receiver on the right ear, (3) FM receiver on the left ear, and (4) bilateral FM system. Results: The results of this study suggested that the slightly modified AAA real-ear measurement procedures resulted in a valid fitting of one FM system on children with normal hearing. On average, prescriptive targets were met for 1000, 2000, 3000, and 4000 Hz within 3 dB, and maximum output of the FM system never exceeded and was significantly lower than predicted uncomfortable loudness levels for the children. There was a minimal change in the real-ear unaided response when the open-ear FM receiver was placed into the ear. Use of the FM system on one or both ears resulted in significantly better speech recognition in noise relative to a no-FM condition, and the unilateral and bilateral FM receivers resulted in a comfortably loud signal when listening in background noise. Conclusions: Real-ear measures are critical for obtaining an appropriate fit of an FM system on children with normal hearing.

Enhancement of Word-Recognition Performance With a Filtering Technique

1991 ◽  
Vol 34 (6) ◽  
pp. 1436-1438 ◽  
Author(s):  
Richard H. Wilson ◽  
John P. Preece ◽  
Courtney S. Crowther
Keyword(s):  
Word Recognition ◽  
Sound Pressure ◽  
Recognition Performance ◽  
Notch Filter ◽  
Normal Hearing ◽  
Broadband Noise ◽  
Female Speaker ◽  
Sound Pressure Levels ◽  
Filtering Technique ◽  
Notch Filtering

The NU No. 6 materials spoken by a female speaker were passed through a notch filter centered at 247 Hz with a 34-dB depth The filtering reduced the amplitude range within the spectrum of the materials by 10 dB that was reflected as a 7.5-vu reduction measured on a true vu meter. Thus, the notch filtering in effect changed the level calibration of the materials. Psychometric functions of the NU No. 6 materials filtered and unfiltered in 60-dB SPL broadband noise were obtained from 12 listeners with normal hearing. Although the slopes of the functions for the two conditions were the same, the functions were displaced by an average of 5 8 dB with the function for the filtered materials located at the lower sound-pressure levels.

Interrupted Monosyllabic Words: The Effects of Ten Interruption Locations on Recognition Performance by Older Listeners with Sensorineural Hearing Loss

2017 ◽  
Vol 28 (01) ◽  
pp. 068-079
Author(s):  
Richard H. Wilson ◽  
Kadie C. Sharrett
Keyword(s):  
Hearing Loss ◽  
Word Recognition ◽  
Sensorineural Hearing Loss ◽  
Repeated Measures ◽  
Recognition Performance ◽  
Sensorineural Hearing ◽  
Repeated Measures Design ◽  
Monosyllabic Words ◽  
Word Onset ◽  
Temporal Location

AbstractTwo previous experiments from our laboratory with 70 interrupted monosyllabic words demonstrated that recognition performance was influenced by the temporal location of the interruption pattern. The interruption pattern (10 interruptions/sec, 50% duty cycle) was always the same and referenced word onset; the only difference between the patterns was the temporal location of the on- and off-segments of the interruption cycle. In the first study, both young and older listeners obtained better recognition performances when the initial on-segment coincided with word onset than when the initial on-segment was delayed by 50 msec. The second experiment with 24 young listeners detailed recognition performance as the interruption pattern was incremented in 10-msec steps through the 0- to 90-msec onset range. Across the onset conditions, 95% of the functions were either flat or U-shaped.To define the effects that interruption pattern locations had on word recognition by older listeners with sensorineural hearing loss as the interruption pattern incremented, re: word onset, from 0 to 90 msec in 10-msec steps.A repeated-measures design with ten interruption patterns (onset conditions) and one uninterruption condition.Twenty-four older males (mean = 69.6 yr) with sensorineural hearing loss participated in two 1-hour sessions. The three-frequency pure-tone average was 24.0 dB HL and word recognition was ≥80% correct.Seventy consonant-vowel nucleus-consonant words formed the corpus of materials with 25 additional words used for practice. For each participant, the 700 interrupted stimuli (70 words by 10 onset conditions), the 70 words uninterrupted, and two practice lists each were randomized and recorded on compact disc in 33 tracks of 25 words each.The data were analyzed at the participant and word levels and compared to the results obtained earlier on 24 young listeners with normal hearing. The mean recognition performance on the 70 words uninterrupted was 91.0% with an overall mean performance on the ten interruption conditions of 63.2% (range: 57.9–69.3%), compared to 80.4% (range: 73.0–87.7%) obtained earlier on the young adults. The best performances were at the extremes of the onset conditions. Standard deviations ranged from 22.1% to 28.1% (24 participants) and from 9.2% to 12.8% (70 words). An arithmetic algorithm categorized the shapes of the psychometric functions across the ten onset conditions. With the older participants in the current study, 40% of the functions were flat, 41.4% were U-shaped, and 18.6% were inverted U-shaped, which compared favorably to the function shapes by the young listeners in the earlier study of 50.0%, 41.4%, and 8.6%, respectively. There were two words on which the older listeners had 40% better performances.Collectively, the data are orderly, but at the individual word or participant level, the data are somewhat volatile, which may reflect auditory processing differences between the participant groups. The diversity of recognition performances by the older listeners on the ten interruption conditions with each of the 70 words supports the notion that the term hearing loss is inclusive of processes well beyond the filtering produced by end-organ sensitivity deficits.

Word-Recognition Performance in Interrupted Noise by Young Listeners with Normal Hearing and Older Listeners with Hearing Loss

2010 ◽  
Vol 21 (02) ◽  
pp. 090-109 ◽  
Author(s):  
Richard H. Wilson ◽  
Rachel McArdle ◽  
Mavie B. Betancourt ◽  
Kaileen Herring ◽  
Teresa Lipton ◽  
...  
Keyword(s):  
Young Adults ◽  
Hearing Loss ◽  
Duty Cycle ◽  
Recognition Performance ◽  
Experimental Studies ◽  
Normal Hearing ◽  
Current Data ◽  
Speech In Noise ◽  
Duty Cycles ◽  
Continuous Noise

Background: The most common complaint of adults with hearing loss is understanding speech in noise. One class of masker that may be particularly useful in the assessment of speech-in-noise abilities is interrupted noise. Interrupted noise usually is a continuous noise that has been multiplied by a square wave that produces alternating intervals of noise and silence. Wilson and Carhart found that spondaic word thresholds for listeners with normal hearing were 28 dB lower in an interrupted noise than in a continuous noise, whereas listeners with hearing loss experienced only an 11 dB difference. Purpose: The purpose of this series of experiments was to determine if a speech-in-interrupted-noise paradigm differentiates better (1) between listeners with normal hearing and listeners with hearing loss and (2) among listeners with hearing loss than do traditional speech-in-continuous-noise tasks. Research Design: Four descriptive/quasi-experimental studies were conducted. Study Sample: Sixty young adults with normal hearing and 144 older adults with pure-tone hearing losses participated. Data Collection and Analysis: A 4.3 sec sample of speech-spectrum noise was constructed digitally to form the 0 interruptions per second (ips; continuous) noise and the 5, 10, and 20 ips noises with 50% duty cycles. The noise samples were mixed digitally with the Northwestern University Auditory Test No. 6 words at selected signal-to-noise ratios and recorded on CD. The materials were presented through an earphone, and the responses were recorded and analyzed at the word level. Similar techniques were used for the stimuli in the remaining experiments. Results: In Experiment 1, using 0 ips as the reference condition, the listeners with normal hearing achieved 34.0, 30.2, and 28.4 dB escape from masking for 5, 10, and 20 ips, respectively. In contrast, the listeners with hearing loss only achieved 2.1 to 2.4 dB escape from masking. Experiment 2 studied the 0 and 5 ips conditions on 72 older listeners with hearing loss, who were on average 13 yr younger and more varied in their hearing loss than the listeners in Experiment 1. The mean escape from masking in Experiment 2 was 7 dB, which is 20–25 dB less than the escape achieved by listeners with normal hearing. Experiment 3 examined the effects that duty cycle (0–100% in 10% steps) had on recognition performance in the 5 and 10 ips conditions. On the 12 young listeners with normal hearing, (1) the 50% correct point increased almost linearly between the 0 and 60% duty cycles (slope = 4.2 dB per 10% increase in duty cycle), (2) the slope of the function was steeper between 60 and 80% duty cycles, and (3) about the same masking was achieved for the 80–100% duty cycles. The data from the listeners with hearing loss were inconclusive. Experiment 4 varied the interburst ratios (0, –6, –12, –24, –48, and –∞ dB) of 5 ips noise and evaluated recognition performance by 24 young adults. The 50% points were described by a linear regression (R 2 = 0.98) with a slope of 0.55 dB/dB. Conclusion: The current data indicate that interrupted noise does provide a better differentiation both between listeners with normal hearing and listeners with hearing loss and among listeners with hearing loss than is provided by continuous noise.

Speech Recognition in Multitalker Babble Using Digits, Words, and Sentences

2005 ◽  
Vol 16 (09) ◽  
pp. 726-739 ◽  
Author(s):  
Rachel A. McArdle ◽  
Richard H. Wilson ◽  
Christopher A. Burks
Keyword(s):  
Hearing Loss ◽  
Speech Recognition ◽  
Mixed Model ◽  
Recognition Performance ◽  
Normal Hearing ◽  
Linguistic Complexity ◽  
Item Questionnaire ◽  
The Mean ◽  
Speech Recognition In Noise ◽  
Better Than

The purpose of this mixed model design was to examine recognition performance differences when measuring speech recognition in multitalker babble on listeners with normal hearing (n = 36) and listeners with hearing loss (n = 72) utilizing stimulus of varying linguistic complexity (digits, words, and sentence materials). All listeners were administered two trials of two lists of each material in a descending speech-to-babble ratio. For each of the materials, recognition performances by the listeners with normal hearing were significantly better than the performances by the listeners with hearing loss. The mean separation between groups at the 50% point in signal-to-babble ratio on each of the three materials was ~8 dB. The 50% points for digits were obtained at a significantly lower signal-to-babble ratio than for sentences or words that were equivalent. There were no interlist differences between the two lists for the digits and words, but there was a significant disparity between QuickSIN™ lists for the listeners with hearing loss. A two-item questionnaire was used to obtain a subjective measurement of speech recognition, which showed moderate correlations with objective measures of speech recognition in noise using digits (r = .641), sentences (r = .572), and words (r = .673).

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